Tarmac doesn't let water through. It sends it somewhere. That needs a fall, a kerb or a channel, and an outfall that isn't your front wall. A drive that slopes down to a cottage can look perfect on day one and wet the walls by November. Compaction is the dull part that matters. A thin layer on a loose base cracks into a crazy-paving pattern after one hard winter. Inland, around Collooney, freeze-thaw opens every crack that holds water. Ask how deep the compacted base will be and how thick the top layer is. Ask about the edges. Unsupported edges crumble, and water gets in from the side. Say who uses the drive. Oil deliveries, a trailer or a tractor need more turning room and a heavier build than a family car. Say how wide the entrance is too. On the coast road at Enniscrone, wind-blown sand and salt wear the surface. Mention it. Resin or tarmac isn't right or wrong. Resin handles ponding better. Tarmac is cheaper for big, simple areas. If the tarmac you have is cracked but firm underfoot, read the resurfacing page first.
Ask for base depth, top-layer thickness, how the edges are held, and a sketch of where the water goes.
Length, width, entrance width, the heaviest vehicle that uses it, and whether water already runs toward the house.
Long rural drives around Ballymote and Tubbercurry are where tarmac earns its place, as long as the fall is built in.